Apparatus for the continuous liquid treatment of flexible materials in strip-like form having means for conserving liquid



Aug. 8, 1950 J. H. COOTE ETIAL 2,517,632

APPARATUS FOR THE CONTINUOUS LIQUID TREATMENT OF FLEXIBLE MATERIALS INSTRIP-LIKE FORM HAVING MEANS FOR CONSERVING LIQUID Filed 001;. 25, 19452 Sheets-Sheet 1 3 WM A Tram/E) Aug. 8, 1950 J. H. COOTE ETAL 2,517,632

APPARATUS FOR THE CONTINUOUS LIQUID TREATMENT 0F FLEXIBLE MATERIALS INSTRIP-LIKE FORM HAVING MEANS FOR CONSERVING LIQUID Filed Oct. 25, 1945 2Sheets-Sheet 2 4 TTO/QWEY Patented Aug. 8, 1950 UNITED STATES APPARATUSFOR THE CONTINUOUS LIQUID TREATMENT OF FLEXIBLE MATERIALS IN STRIP-LIKEFORM HAVING MEANS FOR OONSERVING LIQUID Jack Howard Coote, St. JohnsWood, and Arthur Philip Jenkins, Bloomsbury, London, England, assignorsto British Tricolour Processes Limited, London, England, a Britishcompany Application October 25, 1945, Serial No. 624,354 In GreatBritain October 26, 1944 4 Claims.

This invention relates to the liquid treatment of materials instrip-like form, such as cinematograph films, ribbons and tapes and moreparticu larly to the provision of improved apparatus for use therein.

Many of the more important recent developments in colour photographyinvolve treatment of photographic film with expensive reagents which, inthe form in which they are normally used, are extremely liable toundergo de1eterious changes and are thereby rendered useless if they arekept for any length of time. Whilst shallow baths can be used whensingle positives or short lengths of film are being processed the rapidtreatment of long lengths of coloured cinematograph film require the useof baths in which the film can be immersed during travel through thebath if the work is to be carried out at commercially acceptable speeds.This involves the use of large volumes of treating reagents and unlessthese can be entirely used up before deleterious changes have occurredtherein considerable loss of reagent is involved. Some of the mostuseful of recently developed reagents have an extremely limited lifefrom the point of view of the colour processing laboratory whereuniformity and consistency of reproduced colour values understandardized conditions of operation are essential for satisfactoryworking. It accordingly becomes important to work with the smallestpossible bulk of liquid reagent consistent with commercially acceptableprocessing speeds.

Certain attempts have already been made to deal with this problem. Forexample, it has been proposed to pass film, supported on an endlessband, through a series of vertically arranged flattened tubes incountercurrent relationship to a processing reagent. Such an arrangementis, however difficult to utilize owing to the fact that it makes noallowance for the reaction of the processing reagent on the endless bandneither does it allow for the changes in length produced in the filmbeing processed by the reagent. Changes in the length of film, eventhough small in themselves, become important when considerable lengthsof film are being processed and unless means are provided to allow forincrease in length the photographic emulsion may become damaged bycontact with the confining walls of the flattened tubes and so berendered useless.

Modern photographic reagents are widely divergent in character and aflexible band capable of robust construction, which overcomes thedeficiencies of the prior proposals, is extremely economical in thequantity of processing reagent employed, is capable of being used to"treat film at relatively high speeds and is readily adjustable for thetreatment of both standard and substandard films.

According to the present invention apparatus for the liquid treatment ofstrip-like materials, such as cinematograph films, ribbons and tapes,comprises two elongated tanks, disposed one above the other, the lowertank being a closed tank, means within each tank for guiding saidmaterial in strip-like form and two elongated chambers, both inliquid-tight communication with said tanks, of a width small in relationto their length, each of said chambers communicating along the whole ofits length with the bottom of the upper tank and the top of the lowertank in the vicinity of the elongated side walls thereof.

According to a feature of the invention one side wall of the lower tankcontains one or more apertures, provided with liquid-tight closuremeans, which afford ready access to the tank: preferably the wall has asingle elongated aperture therein.

According to a further feature of the invention the means for guidingstrip-like material within each tank is replaceable so that strip-likematerials of diiierent widths may be processed.

According to yet a further feature of the invention tensioning means areprovided for maintaining the strip material taut where it enters thetreating apparatus whilst driving means are provided where thestrip-like material leaves the treating apparatus effective to exert apull on that material.

The present invention provides an apparatus for the liquid treatment ofmaterials in strip-like form which is of simple construction, theoperative parts of which are all readily accessible and in the use ofwhich changes in the length of the film during processing are readilyaccommodated without any tendency for the film to become damaged bycontact with the walls of the apparatus.

The invention will now be described with reference to the followingdrawings illustrating one embodiment thereof and in which:

Fig. 1 is a front view of a film processing tank constructed inaccordance with the invention.

Fig. 2 is a vertical section along the line 2-2 of Fig. 1, and

Fig. 3 is a horizontal section along the line 3-3 of Fig. 1.

Fig. 4 is a schematic drawing illustrating the liquid flow.

In the apparatus shown in the drawings an upper tank I and a lower tank2 are in liquidtight communication the one with the other through twosimilar liquid-tight chambers 3 and 4 of substantially the same lengthas the tanks.

The tanks i and 2 are long in relation to their width and to their depthand are of substantially the same length. The upper tank 6 is providedwith adjustable screw supports and {5 for supporting a shaft 'iAcarrying bobbins l, mounted lengthwise therein and disposed at such alevel that the bobbins i may be readily submerged in a treatingsolution. The lower tank 2 is provided with adjustable screw supports 3and E for supporting a shaft EBA carrying bobbins it and mountedlengthwise therein. The screw supports 5, 6, 8 and 9 are adjustable sothat the shafts and bobbins may be taken out when the apparatus is to becleaned or exchanged for other bobbins when ill-m of a different widthis to be treated. In this way both standard and sub-standard films canbe processed in the same apparatus.

The liquid-tight chambers 3 and i are of narrow cross-section inrelation to their length and are of considerable depth, the preferreddepth being substantially greater than the length of the tanks i and 2.

The walls of the chambers 3 and t strengthened by horizontalstrengthening members it which are welded thereto at suitable verticaldistances apart. These horizontal strengthening members aresymmetrically welded to the opposite walls or the chambers. horizontalsupporting members longer th o the walls of the chambers It, l andsubstantially wider than the maximum distance between. the outside wallsof the chambers i are also pro vided making smooth contact with thewalls or" chambers 3 and i and having their rear edge or edges incontact with the struts ll upon which the whole apparatus is mounted bymeans or the mounting screws 58, MA. The lower tank 2 is furthersupported by means of the bracket it which is mounted upon struts H? bymeans of mounting screws 18A. The horizontal supporting members it alsoserve to maintain the bers 3 and t the correct horizontal distanceapart. A patch plate is inserted between tank l and the struts ill.

The upper tank l is provided in the front wall with a socket 2i throughwhich a thermometer or thermocouple may be inserted so that the temperature of the liquid in the apparatus can be observed at any time.open or may be provided with a lid (not shown) having apertures thereinthrough which the film enters and leaves the apparatus.

The lower tank 2 is closed by a dome shaped cover H which provides aliquid tight closure thereto and this is supported in the closed position by the locking bar l2 which is locked in position by the wing nuti3. Thi arrangement enables the lower tank 2 to be readily opened. andso permits easy access to the interior thereof and to the bobbins H3 atany time. The tank 2 is mounted upon feet 2 3.

The bobbins l and iii are or" such cross-section as to enable the filmto travel through the apparatus without making contact with the walls ofthe chambers 3 and i and are provided with spaced guides it betweenwhich the coils of film pass during its spiral-like passage through theapparatus.

The inner walls of the apparatus should be smooth throughout. Since theapparatus should be made from material which will not become rough incontact with aqueous solutions it is conveniently constructed fromstainless steel or other rust-resisting alloy all joints being made byOne of v The tank i may remain 4 welding and the joints on the insideafterwards ground smooth.

At the point at which the film enters the tank there is mountedtensioning means (not shown) i. e. a compensator, by means of which thefilm is maintained taut during its passage through the apparatus. Thismay consist, for example, of a sprocket feed, a lightly weighted firstpulley and a second pulley.

At the point at which the film leaves the treating apparatus there ismounted a second sprocket or other similar device (not shown) eiTectiVeto pull the film through the apparatus.

The apparatus is also provided with means which will enable the treatingsolution to circulate therethrough. An exit point 22 for liquid isprovided in the end wall of the upper tank I near the point where thefilm leaves the tank. An entry point 23 for liquid is also provided inthe end wall of the lower tank 2. The liquid circuit contains, inaddition, a pump for circulating the liquid, means for withdrawing spentliquid, means for admitting fresh liquid, and, if desired, a heatexchange unit. A convenient arrangement is one in which a portion ofused liquid is withdrawn between the liquid exit point from the uppertank and the pump while fresh liquid is admitted between the pump andthe liquid entry point in the lower tank. The liquid flow circuit isillustrated in Fig. 4 of the drawlngs.

It will be appreciated that by the use of the two narrow elongatedliquid-tight chambers 3 and i a great economy is effected in the volumeof treating liquid in use at any time. It will of course be understoodthat any desired strengthbe employed. to support the narrow, elongatedchambers.

The apparatus be used in the following way for treating film. With thedome-shaped cover ii in. the lower tank 2 open spacing (film basematerial) is threaded through the apparatus, passing, in turn, over thesecond pulley, over the bobbins l in the upper tank downwards, betweenadjacent spacing guides i l on the under bobbin it in the lower tank 2,then upwards, between adjacent spacing guides 56 and over the bobbins lin the upper tank I and so continues its spiral-like passage until finalemergence from the apparatus whence it passes to the sprocket drivewhich draws it through the apparatus. At some point prior to reachingthe second pulley of the compensator the spacing is jointed to the filmwhich is to undergo treatment. This film is drawn from a reel (notshown) by another sprocket driven, thence, about the lightly weightedpulley to the second pulley. The film passes through the apparatus insuch manner that the film base is in contact with the bobbins l and it.Since the compensating device main tains the film taut during its traveithrough the solution the emulsion is positively prevented from cominginto contact with any part of the walls of the process-unit and thusprevented from becoming damaged. Film treating solution is passedthrough the apparatus in countercurrent relation to the horizontaldirection of travel of the film and at any desired temperature.

It will be evident that the apparatus may also be used to treat numerousother materials in strip-like form such as ribbons and tapes such ascellulose nitrate and cellulose acetate in strip form which are to bedyed or impregnated with liquid compositions. in such cases the sprocketdrives are replaced by other means which will serve to pull the stripmaterial from the reel and through the treating solution. Thus thesprocket drives may be replaced by pairs of normally contacting rollersbetween which the strip material passes. Obviously the strip materialmay be made to pass either rapidly or slowly through the treatingsolution in accordance with the requirements of the particularoperation.

Instead of a single cover unit such as the dome-shaped cover it thelower tank 2 may be closed in other ways, for sample, two separateliquid-tight covers may be provided in the front Wall Of the tankadapted to be locked in the closed position in any convenient manner.

What we claim is:

1. Apparatus for the continuous liquid treatment of flexible material instrip-like form comprising two horizontally elongated tanks, onedisposed above the other, separately removable shafts mounted lengthwisein each of said tanks, each adapted to carry rotatable circular guidemeans for said strip material, two pairs of side wall members, each pairconnected together so as to form an elongated chamber open at the topand at the bottom, each chamber being of small width relative to thewidth of said elongated tanks the open upper ends of said chambers beingdirectly connected to the bottom of the upper tank by a liquid-tightconnection and the open lower ends of said chambers being directlyconnected to the top of the lower tank by a liquid-tight connection andso disposed as to enclose the greater part of the plane of the directcommon tangent of said circular guide means in said elongated tanks toallow the striplike material to pass between said guide means inspiral-like form without touching the side walls thereof, the lowerelongated tank being formed with an elongated aperture in one elongatedside wall thereof which extends along substantially that length of saidtank which embraces said guide means and having closure means thereforadapted to be removably secured in liquid-tight manner to said wall toclose said elongated aperture.

2. Apparatus for the continuous liquid treatment of flexible material instrip-like form comprising two horizontally elongated tanks, onedisposed above the other, a shaft removably mounted in the end walls ofeach of said tanks and having mounted thereon a plurality of separatelyand freely rotatable bobbins, the lower tank having an orifice for theadmission of treating liquid, the upper tank having an orifice for theexit of treating liquid, a pump connected to said orifices forcirculating liquid between the two tanks, means for supportingtemperature recording means in one of said tanks, two pairs of side wallmembers, each pair connected together to form an elongated chamber openat the top and at the bottom, each chamber being of small width relativeto the width of said elongated tanks, the open upper ends of saidchambers being directly connected to the bottom of the upper tank by aliquid-tight connection and the lower ends of said chambers beingdirectly connected to the top of the lower tank by a liquid-tightconnection to form an enclosed bath between said upper and lower tanksabout the plane of a common direct tangent between said bobbins, thelower tank being formed with an elongated aperture in one elongated sidewall thereof which extends along that length of said tank within whichare mounted said bobbins and having closure means therefor removablysecured in liquid-tight manner to said wall to close said aperture andlocking means to lock said closure means in closed position.

3. Apparatus for the continuous liquid treatment of flexible material instrip-like form comprising two horizontally elongated tanks, onedisposed above the other, separately removable shafts mountedlength-wise in each of said tanks and adapted to carry circularrotatable guide means for said strip material, two pairs of side wallmembers, each pair connected together to form an elongated chamber openat the top and at the bottom, each chamber being of small width relativeto the width of said elongated tanks, said chambers and tanks beingintegrally connected together to form a unitary tank, each of saidelongated chambers being so disposed as to enclose the greater part ofthe plane of a common direct tangent between said guide means to allowthe strip-like material to pass between said guide means in spiral-likeform without touching said side wall members, the lower elongated tankhaving an elongated aperture in one elongated side wall thereof alongsubstantially that length of said tank which embraces said guide meansand having closure means therefor removably secured in liquid-tightmanner to said wall to close said elongated aperture.

4. Apparatus for the continuous liquid treatment of flexible material instrip-like form which comprises two horizontally elongated tanks, onedisposed above the other, separately removable shafts mounted lengthwisein each of said tanks and each carrying a plurality of separate, freelyrotatable guide means for said strip-like material, two pairs of side:all members, each pair connected together to form an elongated chamberopen at the top and at the bottom, each chamber being of small widthrelative to the width of said elongated tanks, said chambers and tanksbeing integrally connected together to form a unitary tank, each of saidelongated chambers being so disposed as to enclose the greater part ofthe direct path between the guide means in said tanks and the rotatableguide means in the two tanks being so disposed relative to each other asto provide a free spirallike path for the material on its passage aboutsaid guide means, the lower elongated tank having an elongated aperturein one elongated side wall thereof affording direct access to the guidemeans along substantially that length of said tank embracing said guidemeans and having closure means therefor removably secured inliquid-tight manner to said wall to close said elongated aperture andlocking means to lock said closure means in closed position.

JACK HOWARD COOTE. ARTHUR, PHILIP JENKINS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,461,329 Salins July 10, 19231,490,669 I-Iigginson Apr. 15, 1924 1,493,866 Parkes May 13, 19241,974,353 Zollinger Sept. 18, 1934 2,123,445 Leuven July 12, 19382,169,758 Capstaff Aug. 15, 1939 2,342,000 Leshing Feb. 15, 19442,405,645 Duguid Aug. 13, 1946 FOREIGN PATENTS Number Country Date676,823 Germany Mums-.. June 13, 1939

